The embodiments described herein relate generally to electrical machines, and more particularly, to an electrical machine having a volute-shaped housing.
Known residential or commercial forced draft gas-fired systems require air propulsion units. In addition to providing movement of air for forced draft systems, air propulsion units may be used in combination with residential or commercial gas furnaces, humidifiers, water heaters, and hydrogen fuel cells. Such known air propulsion units include motor driven fans and require large, radial motors to operate the fans. These fans include, for example, centrifugal impeller type fans. However, the large radial motors have large space requirements due to their physical size. Using an axial flux motor can reduce the size requirements of the air propulsion unit. However, some know axial flux machines need a large amount of cooling air to cool the electronics of the motor due to the power densities of such known motors.
Such known radial and axial flux motors can require additional space within the forced-draft system to facilitate the cooling systems needed to keep the motors cool. Such cooling systems can be separate or integral to such motors. The cooling systems further add to the air propulsion unit thickness and introduce weight and complexity to the air propulsion unit. Furthermore, the cost is increased in such air propulsion units due to the increased part count required for coupling a cooling assembly to the motor.
In addition, many known air propulsion units include an integrated controller attached to an end of the unit, thereby further increasing the thickness of the air propulsion unit. To reduce the thickness of the air propulsion unit, many known units include complex controller board arrangements and layouts that can add cost and complexity to the unit, and introduce localized heating from the heat generating components that is not adequately dissipated.